Sökning: "Species-traits"

Visar resultat 1 - 5 av 18 avhandlingar innehållade ordet Species-traits.

  1. 1. The importance of search behavior and movements for spatial distributions of herbivorous insects

    Författare :Petter Andersson; Peter Hambäck; Johan Ehrlén; Tomas Roslin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Olfactory search; Habitat heterogeneity; Species-traits; Immigration; Scaling relationships; Patch size; Plant-insect interactions; EAG; Odors; Pheromones; Plant Ecology; växtekologi;

    Sammanfattning : Insect populations commonly show large spatial variation in density, and much variation have been shown to be explained by the search behavior applied by the insect when locating habitat patches. This thesis explores the importance of odor-mediated attraction for immigration rates of herbivorous insects in relation to the size of the patches and the density of host plants within the patches. LÄS MER

  3. 2. Spatial and evolutionary aspects of species diversity, species traits, and human impact with examples from boreal riparian and forest plant communities

    Författare :Mats Dynesius; Umeå universitet; []
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  4. 3. Empirical and theoretical studies of population trends and extinction risks

    Författare :Tobias Jeppsson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Empirical and theoretical approaches are needed to solve the current problem of increased extinction risk for many species. Thus, this thesis focuses on: (1) ways to estimate population trends for a large number of species, and (2) a predictive framework for identifying vulnerable populations from species traits or life history traits to allow for more proactive conservation actions. LÄS MER

  5. 4. Metapopulation and metacommunity processes, dispersal strategies and life-history trade-offs in epiphytes

    Författare :Swantje Löbel; Håkan Rydin; Tord Snäll; Lars E. Ericson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asexual; biodiversity; bryophytes; dispersal limitation; establishment; evolution of reproductive traits; germination; growth; habitat fragmentation; landscape dynamics; local processes; patch-tracking; pH; reproduction; species richness; species interactions; Other biology; Övrig biologi; Ecological Botany; Ekologisk botanik;

    Sammanfattning : The aim of this thesis was to increase knowledge about metapopulation and metacommunity processes in patchy, dynamic landscapes, using epiphytic bryophytes as a model system. Host trees and deciduous forest stands in the coniferous landscape are patchy, temporal and undergo changes in habitat quality during succession. LÄS MER

  7. 5. Olfactory cues and insects - scaling relations and immigration rates

    Författare :Petter Andersson; Stockholms universitet; []
    Nyckelord :växtekologi; Plant Ecology;

    Sammanfattning : For herbivorous insects, location of host plants and habitat patches strongly depend on the type of sensory cue that is used during the search process and the probability of detecting a patch depends on the relative attraction between patches of different size. The visual impression of a patch increases predictably with the patch diameter and consequently, immigration rates of visually searching insects are often predicted by the scaling to patch size of visual cues. LÄS MER